Preparation of sulphon chlorides



Patented'Jan. 15, 1946 UNITED STATE S PATENT OFFICE PREPARATION OF SULPHON CHLORIDES Stanley R. Detrick, Wilmington, Del., and Lyle A. Hamilton, Pitman, N. J assignors to E. I. du Pont de Nemours & Company, Wilmington, DeL, a corporation of Delaware No Drawing. Application January 15, 1944,

Serial No. 518,404

18 Claims.

, the reaction and particularly the yield therefrom and the control thereof. Many of such modifications have been described in patents, of which Patents 2,193,824 and 2,202,791 are illustrative. Furthermore, M. S. Kharasch, in his application Serial No. 291,515 filed August 23, 1939, discloses that he has found that sulphuryl chloride can be substituted for the mixture of sulphur dioxide and chlorine in such reaction.

It has been found that iron, present even in traces as ferric chloride, iron rust or metallic iron, acts as an anti-catalyst in the reaction, materially retarding the rate of the reaction and producing products of darker color and higher chlorine content that is desired. This effect of iron is recognized in Patent 2,202,791, wherein it is pointed out that the reaction vessel should not be constructed of materials, such as stainless steel, iron, aluminum, copper, copper alloys and the like.

This effect of iron is shown further by the following experiment: In a glass flask, 300 grams of a fully refined paraffin wax of 49 C. melting point was heated to 60 C. and to it was added 200 milligrams of ferric chloride. A mixture of approximately 70 grams per hour of chlorine and 100 grams per hour of sulphur dioxide was :passed into the melted wax until it gained about two-thirds in weight. During this time, the reaction flask was illuminated with a l50-watt incandescent light and the temperature was kept at about 60 C. with external cooling. A portion of the sulphon chloride washydmlyzed with a 50% aqueous solution of sodium hydroxide and a portion was analyzed for sulphur and chlorine, after removal of dissolved sulphur dioxide and chlorine by blowing with nitrogen for three hours.

The results are shown in the table below in comparison with a similar run made without any ferric chloride.

Ferric No ferric chloride chloride Time of reaction ..minutes.. 360 144 Weight of sulphon chloride "grams. 479 487 Atomic ratio 2. 7 1.4

(l reacting to sulphon chloride per hour grams. l4 49 Color of hydrolyzed product Very dark Very light This shows that ferric chloride retards the reactions, causes an increase in the chlorination on the carbon chain and causes a much darker color of the sodium salt.

When it is attempted to carry out the reaction on a commercial scale, the reaction proceeds slowly and the products are dark colored and more highly chlorinated than desired, even though the reaction is carried out in a reaction vessel which does not contain iron or other objectionable. metals. Applicants believe that the difllculty is due to the carrying of small amounts of iron into the reaction vessel from the gas lines which conduct the sulphur dioxide and chlorine to the reaction vessel. However, applicants do not wish to be limited to any theory as to the cause of the dificulty of carrying out this reaction on a commercial scale.

It is an object of the present invention to obtain a more eficient reaction and a better quality of product when producing sulphon chlorides on a commercial scale. Another object is to provide a method for more satisfactorily carrying out the reaction in the presence of iron. A further object is to provide a method for overcoming the anti-catalytic action of iron in this reaction. A still further object is to enable the carrying out of the Reed reaction in equipment made in whole or in part of iron or steel. Other objects are to advance the art. Still other objects will appear hereinafter.

The above and other objects may be accomplished in accordancewith our invention by reacting sulphuryl chloride or a mixture of chlorine and sulphur dioxide with an organic compound devoid of phosphorus in the presence of a small proportion of an from an acid of phosphorus.

organic compound containing the radical of an acid of phosphorus. We have found that, when the reaction is carried out in the presence of an organic compound containing a radical of an acid of phosphorus, particularly on a commercial scale, the rate of the reaction is very materially increased and the products obtained are lighter in color and less highly chlorinated than when the reaction is carried out in the absence of such compound. we have particularly found that such compounds of the acids ofphosphorus are very effective to overcome the anti-catalytic effect of iron to such an extent as to permit carrying out the reaction in equipment composed wholly or in part of steel or iron.

We have found that the organic compounds containing a radical of an acid of phosphorus are effective to improve the reaction when the reagent is either sulphuryl chloride or a mixture of chlo-' rine and sulphur dioxide. Preferably, the sulphur dioxide and the chlorine are employed in the proportions and under the conditions described in Patents 2,193,824 and 2,202,791, although they may be further varied in the manner known to the art.

The starting materials, or organic compounds which are to be converted to sulphon chlorides, may be any of those proposed by Reed in his patents hereinbefore mentioned, ,or proposed by others skilled in the art as in the following patents: 2,174,492, 2,174,505, 2,174,506, 2,174,507, 2,174,508, 2,174,509, 2,193,824, 2,197,800, 2,202,791, 2,212,786, 2,263,312 and 2,321,022. The starting material should be devoid of phosphorus, in order to distinguish such starting material from the organic compound, containing a radical of an acid of phosphorus, which is added to improve the reaction. Preferably, the starting materials, to be converted to the sulphon chlorides, are saturated aliphatic compounds containing at least 8 carbon atoms. Such aliphatic compounds may be straight-chain or branched-chain acyclic compounds or cyclic aliphatic compounds. This invention is rticularly concerned with the treatment of sa urated aliphatic hydrocarbons of 8 or more carbon atoms and especially with the treatment of paraflin wax.

The organic phosphorus compounds, which are to be employed in accordance with our invention, may each be broadly defined as an organic compound which contains the radical of an acid of phosphorus. By the term a radical of an acid of phosphorus, we mean the radical which may be derived by the removal of one or more hydrogens Suitable compounds are those which may be represented by the formula wherein R represents an aliphatic, aromatic, aliphatic oxy or aromatic oxy radical; It represents hydrogen or an aliphatic or aromatic radical; R" represents hydrogen or an aliphatic or aromatic radical; M represents P or the group P=X and X represents oxygen or sulphur.

The compounds within such formula are organic phosphonic acids, organic thiophosphonic acids, organic phosphinic acids, organic thiophosphinic acids and organic esters of phosphoric, thiophosphorlc, phosphorous, thiophosphorous.

aaoaeu phosphonic, thiophosphonic. phosphinic and thiophosphinic acids. Particularly satisfactory results have been obtained with the organic esters of the acids of phosphorus and particularly with the esters of orthophosphoric acid. of such esters, we particularly prefer the aliphatic esters in which the aliphatic group contains at least 8 carbon atoms and especially wherein the aliphatic group is an acyclic hydrocarbon radical. Representative of the most desirable esters are the Loror' phosphates and particularly a mixture of monoand di-Lorol phosphates. The "Lorol" phosphates are obtained by reacting Lorol" alcohol with an esterifying derivative of an acid of phosphorus. L-orol" alcohol is a mixture of alcohols of from 10 to 18 carbon atoms obtained by the fractionation of the mixture of alcohols resulting from the reduction of cocoanut or palm kernel oils.

Quite satisfactory results have also been obtained with the organic esters of phosphorous acids and particularly with the aliphatic phosphites such as tributyl phosphite. Particularly satisfactory results have also been obtained with the organic phosphinic acids and especially with the aryl phosphinic acids, such as benzene phosphinic acid.

The amounts of the organic phosphorus compounds, which should be employed, will depend largely on the amount of iron present and to some extent on the activity of the particular phosphorus compound and on other conditions. The phosphorus compounds of our invention are not equally effective under all conditions and the relative effectiveness of the different compounds will vary with variations in the conditions. It will generally be desirable to employ the phosphorus compound whichis most soluble in the starting material and which will give the highest concentration of phosphorus acid radical. In general, the phosphorus compound will be employed in the proportion of from 0.1% to about 1% of the starting material, but as much as 5% may be employed. Larger amounts maybe used in some cases, but will generally be undesirable as excessive amounts are wasteful, uneconomical and may constitute an undesirable contaminant in the final product,

In a glass flask, 300 grams of a fully refined parafiin wax of 123-125 A. M. P. (American melting point) was heated to 60 C., and to it were added 72 milligrams of ferric chloride and 600 milligrams of a mixture of monoand di-Lorol phosphates (the Lorol radical being derived from commercial Lorol alcohol which is a mixture of alcohols containing from 10 to 18 carbon atoms). .A mixture of chlorine and sulphur dioxide gases was then passed into the melted wax at the rate of approximately grams per hour of chlorine and approximately grams per hour of sulphur dioxide until the wax had gained about two-thirds of its original weight. During for sulphur and chlorine.

this time the reaction flask was illuminated with a 150-watt incandescent light and the temper ature was kept at 60 C. by external cooling. A portion of the resulting sulphonchloride was hydrolyzed to the sodium salts of the corresponding sulphonic acids with a- 50% aqueous solution of sodium hydroxide and a portion was analyzed The results are shown in the table below in comparison with a similar run, made without the addition of the mixture of Lorol phosphates.

p ates With Without Time of reaction hnurs.- 2 t Weight 01 sul hou chloride grams 493 504 Atomic ratio 1.39 1. 74 Cl reacting to sulphon chloride per hour grams 62 39 Color of crude hydrloysis mass Light Dark These results show that, in the presence of crease in the rate of reaction, a decrease in the chlorination on the carbon chain and a lighter color of the crude sodium sulphonate.

When the above comparison was repeated, using 2 grams of steel turnings instead of 72 mg. of ferric chloride, a similar improvement resulted from the addition of Lorol phosphate.

Likewise, when the experiment was repeated, using 600 grams of carbon tetrachloride as a solvent for thewax and keeping the temperature at 25 C., qualitatively similar results were obtained.

Example 2 In a similar manner, 300 grams of cetane, con- \taining 200 milligrams of ferric chloride and 600 milligrams of the mixed Lorol phosphates, was treated with sulphur dioxide and chlorine at 25 C. The following results'were obtained in comparison with a similar run, made without In a glass flask fitted with agitation and a reflux condenser, 300 grams of fully refined parafiln wax of 123-125 A. M. P. was heated to 60 C. and to it was added 1 gram stearamide,

200 milligrams ferric chloride and 600 milligrams of mixed Lor'ol phosphates. Then 435 grams of sulphuryl chloride was gradually added during about 2 hours. During this time, the flask was illuminated with an incandescent electric light and the heat of the reaction kept the temperature at 65 C. to 67 C. with a slight refluxing of sulphuryl chloride. At the end of the reaction, excess sulphuryl chloride was distilled out and the sulphon chloride wasanalyzed. The results, in comparison with a similar run without the Loi-ol" phosphates, are as follows:

ferric chloride, Lorol phosphate causes an in- Lorol" phosphates With Without Sul hur percent.. 3. 2. 04 Ch orine 1.... d 17. 94 12.96 Atomic ratio 4. 6 5. 4

It is, therefore, apparent that, in the presence of ferric chloride, the IoroP phosphate mixture caused a more eflicient reactionto form sul- Dhon chloride.

Example 4 When Example 1 was repeated, using 200 milligrams of ferric chloride (instead of 72 milligrams) and 600 milligrams of tributyl phosphite (instead of Lorol phosphate) the results were as follows:

Trlbutyl phosphitc With Without Time of reaction minutes 138 u 360 Weight of sulphon chloride grams 502 479 Atomic ratio 1. 4 2. 7 Cl reacting to sulphon chloride per hour grams 53 14 Color of crude hydrolysis mass Light Very dark Example 5 Example 4 was repeated, using benzene phosphinic acid in place of tributyl phosphite, with the following results:

Benzene phosphinic acid With Without Time of reaction "minutes. 135 60 Weight of sulghon chloride ngramsn 502 479 Atomicmtb 1.5 2. 7 Ci reacting to sulphon chloride per hour 56 14 Color of crude hydrolysis mass Light Very dark Example 6 Example 1 was repeated, but, instead of 72 milligrams of ferric chloride, two test strips of cold rolled steel were placed in the flask. These test strips were approximately 25 x 12 x 3 millimeters in size and they weighed 7.4510 and 7.4760 grams respectively. The experiment was run several times in the same fiasl: until the steel pieces had been exposed to the reaction for 68 hours. It

- was then found. that one piece had lost 13 milligrams and the other 13.5 milligrams, which represents a penetration of 0.27 millimeters or 0.01 inch per year. The middle run of sulfon chloride, which is typical of the whole series, gave a weight of 500 grams in 125 minutes, having an atomic ratio of sulphur chlorine of 1.46. The weight of chlorine, reacting per hour to give sulphon chloride, was 56 grams and the hydrolyzed mass was tan colored. In the absence of the Lorol" phosphate, the reaction was much retarded and the product was very dark in color.

Example 7 In a glass flask under illumination, 500 grams of fully refined paraflin wax, melting at 49 C.

' and containing 5 grams of the mixture of monoand di-LoroP' phosphates used in Example 1,

was treated with a mixture of chlorine and suiphur dioxide gases at a rate approximately 30 grams chlorine and 60 grams sulphur dioxide per hour for about 14 hours at 60 C. to 65 C. During this time, the reaction mixture was circulated, by means of a glass pump, through an external heat exchanger which included a steel pipe 46 cm. in length and 0.95 cm. internal diameter. After the completion of the reaction,-the batch was allowed to remain in the apparatustor about 9 hours. It was then removed and another batch was run in the same way. This series of batch runs was continued until the iron pipe was exposed for days to the combined corrosive action of the sulphur chloride and the dissolved chlorine, sulphur dioxide and hydrogen chloride. During the later runs of this series, the amount of Lorol phosphate in the wax was reduced from 1% to 0.5% and 0.25%, without any apparent eiiect on the efliciency of the reaction or the quality of the product. After the 10 days exposure. the steel pipe had lost 284 milligrams weight, which correspond to a penetration of 0.1 millimeter; or 0.004 inch per year. Different samples of sulphur chloride, obtained in this series of runs, contained from 10 to 80 parts per million of iron. The highest amount found represents a penetration of 0.24 millimeters or 0.0095 inch per year. This experiment demonstrates that steel may be used in the construction of certain parts of the equipment used in the,process when phosphorus compounds are employed in accordance with our invention.

The formulae of the organic phosphorus .com-

pounds, used in the examples, are: Example 1:

on on o=ron and 0=PO-Lorol" 0--Lorol" O-Lorol" Example 2: Same as Example 1. Example 3: Same as Example 1.

Example 6: Same as Example 1. Example 7 Same as Example 1.

tri-Lorol phosphite P(OC12H25)3, tri-Lorol thiophosphate (C1:Ha5O)aP=S dicetyl phosphate (CisI-IaaOh-PO'OH, tri-Lorol phosphate I monoand di-Lorol" thiophosphate,

C12H25O'PS' (SH) 2 and (CmHzsO) zPS-SH tri-cresyl phosphate (C1HaO)a-P=O, diphenyl phosphate (CeHsOh-PO-OH diamino phenyl phosphate CeHsO-PO- (NH2) 2 and lecithin Phosphoric acid and mono sodium phosphate were "also found to partly prevent the harmful eflect of iron in the reaction of chlorine and sulphur dioxide on wax. However, they are less desirable to use for this purpose since they are not appreciably soluble in aliphatic oils and waxes and, therefore, they are not forced into contact with all iron surfaces and furthermore they leave an insoluble residue to be separated from the sulphon chloride.

It will be understood that the preceding examples are given for illustrative purposes solely and that our invention is not to be limited to the speciflc embodiments disclosed therein, but that many variations and modifications can be made in the phosphorus compounds, in the starting materials and in the condition employed without departing from the spirit or scope of our invention. Accordingly, we intend to cover our invention broadly as in the appended claims.

It will be apparent that our invention is of substantial valuein improving the commercial production of organic sulphon chlorides, particularly where the reacting materials may be contaminated with small amounts oi! iron. Our invention makes it possible to conduct the reaction in the presence of iron or steel without appreciable loss of efiiciency of the reaction or quality of the product; Our invention makes it possible to design more economical and practical equipment since all or parts of the equipment may be made from steel instead of the more expensive and less common materials, such as nickel, nickel clad steel and Monel metaL More particularly, by our invention, we are able to obtain an important increase in the rate of reaction while obtaining a decrease in the chlorination and a lighter color in the final product.

We claim:

1. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a, mixture of chlorine and sulphur dioxide with organic compounds devoid of phosphorus, the improvement which comprises carryingout the reaction in the presence'of a small proportion of a compound of the group consisting of organic phosphonic acids, organic thiophosphonic acids, organic phosphinic acids, organic thiophosphinic acids and organic esters of phosphoric, thiophosphoric, phosphorous, thiophosphorous, phosphonic, thiophosphonic, phosphinic and thiophosphinic acids.

2. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic compounds containing at least 8 carbon atoms but devoid of phosphorus, the improvement which comprises carrying out the reaction in the presence of a small proportion of a compound of the group consisting of organic phosphonic acids, organic thiophosphonic acids, organic phosphinic acids, organic thiophosphinic acids and organic esters of phosphoric, thiophosphoric, phosphorous, thiophosphorous, phosphonic, thiophosphonic, phosphinic and thiophosphinic acids.

3. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a. mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 5 carbon atoms the improvement which comprises carrying out the reaction in the presence of a small proportion of a compound of the group consisting of organic phosphonic acids, organic small proportion of a mixture monoand dithiophosphonic acids, organic phosphinic acids, organic thiophosphinic acids and organic esters of phosphoric, thiophosphoric, phosphorous. thiophosphorous, phosphonic, thiophosphonic, phosphinic and thiophosphinic acids.

4. In the process of preparing sulphon chrides by reacting a member of the group consisting of sulphuryl chloride and a. mixture of chlorine and sulphur dioxide with parafiin wax, the improvement which comprises carrying out the reaction in the presence of a small proportionof a compound of the group consisting of organic phosphonic acids, organic thiophosphonic acids, organic phosphinic acids, organic thiophosphinic acids and organic esters of phosphoric, thiophosphoric, phosphorous, thiophosphorous, phosphohic, thiophosphonic, phosphinic and thiophosphinic acids.

5. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of an organic ester of an acid of phosphorus.

6, In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms,- the improvement which comprises carrying out the reaction in the presence of a small proportion of an organic ester of a phosphoric acid.

'7. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of an organic ester of orthophosphoric acid.

8. In the process of preparing sulphon chlorides byreacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of asmall proportion of an aliphatic esterof orthophosphoric acid in which the aliphatic group contains at least 8 carbon atoms.

9. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of an aliphatic ester of orthophosphoric acid in which the aliphatic group is an acyclic hydrocarbon radical containing at least 8 carbon atoms.

10. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the' reaction in the presence of a aliphatic esters of ortho-phosphoric acid in which each aliphatic group is an acyclic hydrocarbon radical containing at least 8 carbon atoms.

11. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing a least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of Lorol phosphates.

12. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms. the improvement which comprises carrying out the reaction in the presence of a small proportion of a mixture of monoand di-Lorol phosphates.

13. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least}; carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of an organic ester of a phosphorous acid.

14. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of an aliphatic ester of phosphorous acid.

15. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulfuryl chloride and a mixture of chlorine and sulfu dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of tributyl phosphite.

16. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chlorine and sulphur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of an organic phosphinic acid.

17. In the process of preparing sulphon chlorides by reacting a member of the group consisting or sulphuryl chloride and a mixture of chlorine and sulphur dioxide With saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of an aryl phosphinic acid.

18. In the process of preparing sulphon chlorides by reacting a member of the group consisting of sulphuryl chloride and a mixture of chicrine and sulfur dioxide with saturated aliphatic hydrocarbons containing at least 8 carbon atoms, the improvement which comprises carrying out the reaction in the presence of a small proportion of benzene phosphinic acid.

STANLEY R. DE'IRICK. LYLE A. HAMILTON.

Certificate of Correction Patent No. 2,392,841. January 15, 1946,

STANLEY R. DETRIGK ET AL.

It is hereby certified that errors appear in the printed specification of the above numbered patent re' uiring correction as follows: Page 1, second column, lines 15-16, for reactions rea reaction; page 2, second column line 42, after from insert about; page 3, first column, line 21, in the table, first column thereof, for hydrloysis read hydrolysis; page 4, first column, lines 15 and 25, for sulphur read sulfon; same page secon column lines 42, 55, and 69, page 5, first column, lines 8, 21, 30, 39, 49, 59, and 70, and second column, lines 8, 16, 24, 32, 49, 57, and 65, for sulphury read mlfuryl; same page 5 second column, line 10, for a least read at least; and that the sai Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 23d day of April, A. D. 1946.

[sun] LESLIE FRAZER, I

First Assistant Commissioner of Patents. 

